Hi,
First things first… awesome game – enjoying it very much! 
One thing that would be nice to see would be a journal or bestiary of encountered enemies (perhaps tucked into it’s own panal within the ‘Hero’ menu). Basically a sort of compendium where a player could view an (possibly animated) enemy 3D model that he/she has already encountered (including bosses) and it would list some attributes of that particular enemy such as name, known attacks/defenses and the areas encountered. Furthermore it may also be broken down by ‘type’ of enemy with show/hide handles, similar to the crafting dialog’s known recipes list. One other suggestion may be that the ‘known attacks/defenses’ of a given enemy might not all be populated until a player encounters the enemy over several instances, in order to complete that particular creature’s journal entry.
This bestiary should ultimately serve 2 major purposes – the first being that it’s just plain fun to try to ‘collect them all!’ and have an ever-growing list of monsters to view & admire the details put into the characters that may not be easily apparent in quick-action fights.
Second, it would help players have a quick in-game reference to not only where to look for more of said enemy (say for possible loot/mats collection or otherwise) without having to temporarily interrupt or minimize the game and hitting the internet for the very same info already coded to the enemy, but give players a quick reminder spec/defend against previously encountered foes & bosses.
Hope this helps,
Keep up the awesome work Arenanet!